Method of separating polymers of



Patented July 8, 1947 UNITE ,srArE s PATENT orrica METHOD OF SEPARATING POLYMERS OF HEAT POLYlVIERIZED DRYING 01L Isidor M. Bernstein,

mesne assignments, to

Inc., Brooklyn, N.

Brooklyn, N. Y., assignor, by H. D. Roosen Company Y., a corporation of Delaware No Drawing. Application August 29, 1944,

Serial No.

4 Claims. (Cl. 260-4285) This invention relates to the selective separation of polymers of different molecular weights occurring in heat polymerized drying and semidrying vegetable and fish oils known as stand ovide separation a novel oils and has for an object to pr products having novel properties and and improved method of obtaining the same.

The present invention provides a. method by may be separated into two, three, four, or five fractionsof progressively inthe number of fracthe extent of the heat polymerization of the drying or semi-drying oil. Such which stand oils creasing molecular weight tions depending on primary alcohols from C3 to Ca in length inclusive pos only for the monomeric for the various p merization process. The selective solubility the progressively polymers in the se mary alcohols bon chain length of the alcohols.

Thus, for example in a sample of a 585 heat polymerized lins ity of approximately hol at room all the remaining monomeric, substantially all th meric, N-amyl alcohol substantially all the line and branched trimeric, an stantially all the linear an linseed oil molecules from the successive r mainders of the stand oil.

180 poises, N-propyl alc higher polymers which may be further purified 45 ample pentaerythritol and mannitol, with the by extraction with petroleum ether (so-'60 c. d ying oil or semi-dryi g oil fatty aci of the 011s.

boiling range) or other light fraction petroleum l sted abovenaphtha in the boiling range of 20-130 C. The following is a e ample of my fractional It is of course obvious that only in a highly Separation P polymerized "standexample will it be possible to tions. It the drying or seminon-livering properties pigments such e Mineral, etc., and in .the paint and varnish inor drying properties. is based on the discovery that the homolgous series of saturated aliph'atic arbon chain sess difierent solubilities not oil molecules remaining at any stage of the heat polymerization but also olymers of progressively increasing molecular weight formed by the. heat polyincreasing molecular weight ries of saturated aliphatic pricorresponds with increase in careed oil carried to a viscostemperature extracts substantially N-butyl alcohol e linear and branched did N-hexyl-alcohol subd branched tetrameric The final residue consists substantially of insoluble cross-linked.

oil such as in the above separate five fracdrying oil has not been polymerized past the dimeric stage only the N-propyl alcohol monomeric, and the N-butyl alcohol dimeric separations will be possible. Likewise if the oil has not b the trimeric stage, only the the N-butyl dimeric, separations can be eflected.

The method may lined above, a sample polymers together as onemainder of ry and/or semi-drying oils, or with N-amy meric, dimeric, and trime mainder. in different sequences as desired.

peraturerange of 450 oil used, on the presenc the presence of alysts as is well known in the art.

ing oils,

or potassium hydroxide jugated drying oils made a natural hydroxylated oil such artificially hydroxylated drying and se oils of the classes esterification of the polyhy een polymerized past N-propyl monomeric, and the N-amyl trimeric be used in an alternate .way. Instead of treating one sample of the viscous stand oil with successive quantities of the various saturated normal aliphatic alcohols asoutof the stand oil may be extracted with N-butyl alcohol which wi l separate substantially the monomeric and dimeric fraction from the rethe more highly polymerized drying l alcohol which will separate substantiallyth'e monoric polymers as one fraction from the more highly polymerized re- Thus the separation may take place The viscous heat polymerized oils referred to herein as stand' oil are those made by the usual heat-polymerization method, 1. e., by heating the drying or semi-drying oil in the tem- F.-600 F. for a sumcient tim interval depending on the reactivity of the e or absence of air and on or absence of polymerization cat- Suitable drying oils for this treatment are (1) emi-drying oils such as linoiticica, soya bean, sunflower (2) the frachighly unsaturated atural drying or semi-dry- (3) isomerized conjugated drying oils such as those made by the treatment with sodium of the above natural drying and semi-drying oils, (4) dehydrated conby the dehydration of as castor oil or of mi-drying above mentioned, and (5) synthesized drying oils such as those made by the v dric alcohols, as for ex- To parts of a viscous. stand oil resulting from the heat" polymerization of linseed oil at an inert atmosphere, are

.400 parts of N- is thoroughly shaken or stirred in a batch operation, or by countercurrent flow method in a continuous operation. The N-propyl alcohol layer is removed. and the residue washed once or more with 400 parts N-propyl alcohol. The combined N-propyl alcohol extracts which'contain substantially all the monomeric oil molecules, are subjected to distillation to recover the N-propyl alcohol and the monomeric oil.

To the residue of the "stand oil'after the N- propyl alcohol extraction, 400 parts or N-butyl alcohol are added, shaken, separated and washed. The combined extracts which contain substan: tially all the dimeric oil molecules, are subjected to distillation to recover the N-butyl alcohol and the dimeric oil. a

The same extraction operation is performed successively with N-amyl alcohol and N-hexyl alcohol to recover substantially all of the trimeric and tetrameric oil respectively. The residue if any consists substantially of cross-linked polyme'rs which may be further extracted with light fraction petroleum naphtha to remove the oily fraction as setforth in my copending application above identified.

It will be understood that certain steps may be omitted if it is not required that each fractionbe separated and that fractions consisting of a selected group of polymers may be obtained.

The other stand oils may be treated in a similar manner and it is to be understood that they may be substituted for linseed oil stand oil in the above example.

Although. a specific embodiment of the invention has been described it is to be understood that the invention is capable of various'uses and that changes and modifications may be made therein as will be apparent to a person skilled in the art. The invention is only to be limited in accordance with the following claims.

urated aliphatic primary alcohol, said alcohol and homologues having from three to six carbon atoms, and separating the respective extractions.

2. The method of separating polymeric fractions of heat polymerized drying' oil which comprises extracting said polymerized oil successively with N-propyl alcohol and its progressively higher.

iliomologues and separating the respective extracons.

3. The method of separating polymeric fractions or heat polymerized linseed oil which comprises extracting said polymerized oil successively with progresively higher homologues of a saturated aliphatic primary alcohol, said alcohol and homoiogues having from three to six carbon atoms, and separating the respective extractions.

4. The method of separating polymeric fraction or heat polymerized linseed oil which comprises extracting said polymerized oil successively with N-propyi alcohol and its progressively higher homologues and separating the respective extractions.

ISIDOR M. BERNS'IEIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,304,074 Cherry Dec. 8, 1942 2,219,862 Bradley Oct. 29, 1940 2,239,692 Behr Apr. 29, 1941 2,166,103 Behr July 18, 1939 

